US7182808B2 - Accelerator admixture - Google Patents
Accelerator admixture Download PDFInfo
- Publication number
- US7182808B2 US7182808B2 US10/544,979 US54497904A US7182808B2 US 7182808 B2 US7182808 B2 US 7182808B2 US 54497904 A US54497904 A US 54497904A US 7182808 B2 US7182808 B2 US 7182808B2
- Authority
- US
- United States
- Prior art keywords
- component
- accelerator composition
- accelerator
- composition according
- sulphate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000203 mixture Substances 0.000 claims abstract description 71
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims abstract description 17
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910021502 aluminium hydroxide Inorganic materials 0.000 claims abstract description 11
- 239000001164 aluminium sulphate Substances 0.000 claims abstract description 11
- 239000004568 cement Substances 0.000 claims abstract description 11
- KRHYYFGTRYWZRS-UHFFFAOYSA-N hydrofluoric acid Substances F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims abstract description 11
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims abstract description 9
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 9
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims abstract description 8
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims abstract description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 6
- -1 aliphatic mono- Chemical class 0.000 claims abstract description 6
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Chemical compound [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 claims abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims abstract description 6
- 239000002184 metal Substances 0.000 claims abstract description 6
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims abstract description 6
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims abstract description 5
- 239000007864 aqueous solution Substances 0.000 claims abstract description 5
- 150000003839 salts Chemical class 0.000 claims abstract description 5
- 125000005263 alkylenediamine group Chemical group 0.000 claims abstract description 4
- 229910052938 sodium sulfate Inorganic materials 0.000 claims abstract description 4
- 235000011152 sodium sulphate Nutrition 0.000 claims abstract description 4
- ISIJQEHRDSCQIU-UHFFFAOYSA-N tert-butyl 2,7-diazaspiro[4.5]decane-7-carboxylate Chemical compound C1N(C(=O)OC(C)(C)C)CCCC11CNCC1 ISIJQEHRDSCQIU-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000006185 dispersion Substances 0.000 claims abstract description 3
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims abstract description 3
- 229910052808 lithium carbonate Inorganic materials 0.000 claims abstract description 3
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 claims abstract description 3
- 239000001095 magnesium carbonate Substances 0.000 claims abstract description 3
- 229910000021 magnesium carbonate Inorganic materials 0.000 claims abstract description 3
- 235000014380 magnesium carbonate Nutrition 0.000 claims abstract description 3
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 claims abstract description 3
- 239000000347 magnesium hydroxide Substances 0.000 claims abstract description 3
- 229910001862 magnesium hydroxide Inorganic materials 0.000 claims abstract description 3
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims abstract description 3
- 235000019341 magnesium sulphate Nutrition 0.000 claims abstract description 3
- 229910000027 potassium carbonate Inorganic materials 0.000 claims abstract description 3
- 235000011181 potassium carbonates Nutrition 0.000 claims abstract description 3
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 claims abstract description 3
- 229910052939 potassium sulfate Inorganic materials 0.000 claims abstract description 3
- 239000001120 potassium sulphate Substances 0.000 claims abstract description 3
- 235000011151 potassium sulphates Nutrition 0.000 claims abstract description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 3
- 235000017550 sodium carbonate Nutrition 0.000 claims abstract description 3
- 229910052783 alkali metal Inorganic materials 0.000 claims description 8
- 150000001340 alkali metals Chemical class 0.000 claims description 8
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims description 8
- 235000011128 aluminium sulphate Nutrition 0.000 claims description 8
- BUACSMWVFUNQET-UHFFFAOYSA-H dialuminum;trisulfate;hydrate Chemical compound O.[Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O BUACSMWVFUNQET-UHFFFAOYSA-H 0.000 claims description 8
- 238000005507 spraying Methods 0.000 claims description 7
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims description 6
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000007921 spray Substances 0.000 claims description 5
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 4
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 3
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 2
- 239000005977 Ethylene Substances 0.000 claims description 2
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 claims description 2
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 claims description 2
- 235000011054 acetic acid Nutrition 0.000 claims description 2
- 239000004480 active ingredient Substances 0.000 claims description 2
- 125000002947 alkylene group Chemical group 0.000 claims description 2
- 235000015165 citric acid Nutrition 0.000 claims description 2
- IRXRGVFLQOSHOH-UHFFFAOYSA-L dipotassium;oxalate Chemical compound [K+].[K+].[O-]C(=O)C([O-])=O IRXRGVFLQOSHOH-UHFFFAOYSA-L 0.000 claims description 2
- 239000012530 fluid Substances 0.000 claims description 2
- 235000006408 oxalic acid Nutrition 0.000 claims description 2
- 235000019260 propionic acid Nutrition 0.000 claims description 2
- ZNCPFRVNHGOPAG-UHFFFAOYSA-L sodium oxalate Chemical compound [Na+].[Na+].[O-]C(=O)C([O-])=O ZNCPFRVNHGOPAG-UHFFFAOYSA-L 0.000 claims description 2
- 229940039790 sodium oxalate Drugs 0.000 claims description 2
- 239000000243 solution Substances 0.000 claims description 2
- 235000002906 tartaric acid Nutrition 0.000 claims description 2
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims 3
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 claims 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 claims 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 claims 1
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 claims 1
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 claims 1
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 claims 1
- 235000019253 formic acid Nutrition 0.000 claims 1
- IUVKMZGDUIUOCP-BTNSXGMBSA-N quinbolone Chemical compound O([C@H]1CC[C@H]2[C@H]3[C@@H]([C@]4(C=CC(=O)C=C4CC3)C)CC[C@@]21C)C1=CCCC1 IUVKMZGDUIUOCP-BTNSXGMBSA-N 0.000 claims 1
- 239000011975 tartaric acid Substances 0.000 claims 1
- 150000001991 dicarboxylic acids Chemical class 0.000 abstract description 2
- 230000007774 longterm Effects 0.000 abstract 1
- 239000000463 material Substances 0.000 description 6
- 239000003513 alkali Substances 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- 239000004567 concrete Substances 0.000 description 3
- 239000004615 ingredient Substances 0.000 description 3
- 150000001399 aluminium compounds Chemical class 0.000 description 2
- 229940077746 antacid containing aluminium compound Drugs 0.000 description 2
- 239000008030 superplasticizer Substances 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 150000004645 aluminates Chemical class 0.000 description 1
- 159000000013 aluminium salts Chemical class 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000003916 ethylene diamine group Chemical group 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 229940039748 oxalate Drugs 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical compound OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 description 1
- BITYAPCSNKJESK-UHFFFAOYSA-N potassiosodium Chemical compound [Na].[K] BITYAPCSNKJESK-UHFFFAOYSA-N 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000011378 shotcrete Substances 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 235000011044 succinic acid Nutrition 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B22/00—Use of inorganic materials as active ingredients for mortars, concrete or artificial stone, e.g. accelerators, shrinkage compensating agents
- C04B22/08—Acids or salts thereof
- C04B22/12—Acids or salts thereof containing halogen in the anion
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/04—Carboxylic acids; Salts, anhydrides or esters thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/10—Accelerators; Activators
- C04B2103/12—Set accelerators
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00034—Physico-chemical characteristics of the mixtures
- C04B2111/00146—Sprayable or pumpable mixtures
- C04B2111/00155—Sprayable, i.e. concrete-like, materials able to be shaped by spraying instead of by casting, e.g. gunite
Definitions
- This invention relates to low alkali and alkali-free accelerators for sprayed cementitious compositions.
- the major problem in the art is to find an accelerator composition that combines acceptable performance, acceptable stability and an acceptable compressive strength. Stability can be a problem, especially in the more extreme conditions sometimes encountered in tunnels, and a reasonable shelf-life is necessary for a practical accelerator. All accelerators used in spraying concrete lower the compressive strength compared to the compressive strength of the same concrete without accelerator. It is necessary that this lowering be kept to a minimum. In addition, a good early strength development in the 1–4 hour period after spraying is particularly desired.
- the invention therefore provides an accelerator composition adapted to be used with sprayed cementitious compositions, which is an aqueous solution or dispersion of a blend of the essential Components 1–3:
- Component 1 aluminium sulphate, may be any aluminium sulphate used in the manufacture of accelerators. It may be fully hydrated, or totally or partially calcined. A typical grade, and the one on which the proportion is based, is “17%” aluminium sulphate (Al 2 (SO 4 ) 3 .14.3H 2 O) (called thus because that is the proportion of aluminium oxide therein). should any other aluminium sulphate be required, he appropriate quantity can be easily calculated on this basis.
- Preferably Component 1 is present in the proportion of from 30–46% by weight of the total accelerator composition.
- Component 2,alkanolamine, alkylene diamine and alkylene triamine may be any such material, but is preferably ethylene diamine, ethylene triamine, diethanolamine or triethanolamine, most preferably diethanolamine. It is preferably present in the proportion of from 0.1–10%, more preferably from 0.1–8%, by weight of the total accelerator composition. It is possible to use a combination of two or more of such materials.
- hydrofluoric acid is generally used as an aqueous solution of about 40% HF by weight.
- the proportion of hydrofluoric acid present in the total accelerator composition is preferably from 2–4% by weight of the total accelerator.
- Component 4 may be selected from among the materials previously named. Although sodium and potassium are alkali metals, the proportion of such metals in the accelerator compositions according to this invention may be sufficiently low to permit these accelerators to be considered as alkali-free according to the accepted European definition (lower than 1% (weight) of Na 2 O equivalent). Up to 8.5% Na 2 O equivalent is considered “low alkali” and is acceptable for many purposes—in many cases, rigorous exclusion of alkali on health and environmental grounds is not necessary and a small proportion of at least one alkali metal enhances the early strength development. Thus, for the purposes of this invention, and contrary to the current practices of the art with respect to alkali-free accelerators, it is preferred that a minor proportion of alkali metal be present. This proportion is preferably no higher than 5% Na 2 O equivalent.
- the preferred proportion of Component 4 is from 1–10% by weight of the total accelerator composition. Component 4 is typically added to the accelerator composition as a 30% weight solution in water.
- Component 5 may be selected from one or more of the group of acids. Especially preferred are formic, oxalic and glycolic acids and their metal salts, but other acids, such as acetic, propionic, succinic, citric and tartaric acids are also useful. Preferred proportions of Component 5 are from 2–10%, more preferably from 4–8%, by weight of the total accelerator composition.
- Component 4 and Component 5 be present in the composition.
- the preferred Components 4 and/or 5 for the purposes of this invention are sodium oxalate, potassium oxalate and mixtures of one or both of these with lithium hydroxide.
- the LiOH/sodium-potassium oxalate mixtures are particularly preferred.
- Component 6 aluminium hydroxide, is preferably amorphous aluminium hydroxide of the type normally used in accelerators for sprayed concrete. It is preferably present in the proportion of up to 10% by weight of the total accelerator composition. It is possible to use crystalline aluminium hydroxide; this is considerably cheaper, but it is difficult to dissolve and it does not perform as well as the amorphous material.
- Component 7 acts as a stabiliser. Although it is possible to omit it, it confers a useful degree of stability on the accelerator compositions of this invention, a vital consideration in tunnelling operations where the accelerator may have to remain in a ready-to-use state for long periods. It is therefore preferably present, and in a concentration of from 0.1–2% by weight of the accelerator composition. It is possible to use a blend of both acids, but it is preferred to use phosphoric acid alone.
- the accelerator compositions may be prepared by simply mixing the abovementioned components in any order and stirring to give an aqueous solution. In some cases, additional water will need to be added.
- the final composition will generally comprise from 40–70% by weight of water.
- the resulting accelerator composition will not be a simple mixture of ingredients but a complex blend of reaction products.
- the HF will react with some other components (most especially aluminium hydroxide, if any be present).
- This composition is very stable, having a shelf life under normal storage conditions of several months.
- the accelerator composition of the invention is injected at a spray nozzle in the conventional manner.
- the dose is typically from 5–12% by weight accelerator composition based on cement weight.
- the invention also provides a method of applying a cementitious composition to a substrate by spraying, comprising the steps of mixing a batch of fluid cementitious composition and conveying it to a spray nozzle, there being injected at the nozzle an accelerator as hereinabove described.
- Sprayed cementitious compositions that utilise accelerator compositions according to this invention exhibit an unusually rapid build-up of compressive strength.
- the accelerator compositions work well with an unusually wide variety of cements, including Japanese cements, with which other alkali-free accelerators give less satisfactory results.
- the invention also provides a hardened cementitious layer applied to a substrate by spraying through a spray nozzle, there having been added at the nozzle an accelerator as hereinabove described.
- a number of accelerators are added to a test mortar mix having the following constitution:
- the cement is Tayheiyo OPC, a commonly-used Japanese cement.
- the superplasticiser used is NT-1000 ex NMB Ltd., Japan.
- Example 1 is repeated, with the exception that the 31.5 parts of the accelerator according to the invention is replaced by a commercially-available alkali-free accelerator sold as MEYCO® SA162.
- Example 1 is repeated, with the exception that the 31.5 parts of the accelerator according to the invention is replaced by a commercially-available alkali-free accelerator sold as MEYCO® SA170.
- composition comprising the accelerator according to the invention develops compressive strength earlier than the compositions comprising the commercial accelerators, and that the final strength is substantially higher.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- Particle Accelerators (AREA)
- Liquid Crystal Substances (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Paints Or Removers (AREA)
- Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB0304158.9A GB0304158D0 (en) | 2003-02-25 | 2003-02-25 | Admixture |
| GB0304158.9 | 2003-02-25 | ||
| PCT/EP2004/001594 WO2004076382A1 (en) | 2003-02-25 | 2004-02-19 | Accelerator admixture |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| US20060137576A1 US20060137576A1 (en) | 2006-06-29 |
| US7182808B2 true US7182808B2 (en) | 2007-02-27 |
Family
ID=9953539
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US10/544,979 Expired - Lifetime US7182808B2 (en) | 2003-02-25 | 2004-02-19 | Accelerator admixture |
Country Status (16)
| Country | Link |
|---|---|
| US (1) | US7182808B2 (no) |
| EP (1) | EP1597214B2 (no) |
| KR (1) | KR101097568B1 (no) |
| CN (1) | CN100404469C (no) |
| AT (1) | ATE435845T2 (no) |
| AU (1) | AU2004215680B2 (no) |
| BR (1) | BRPI0407787B1 (no) |
| CA (1) | CA2516048A1 (no) |
| DE (1) | DE602004021908D1 (no) |
| ES (1) | ES2327924T5 (no) |
| GB (1) | GB0304158D0 (no) |
| MX (1) | MXPA05009033A (no) |
| NO (1) | NO342962B1 (no) |
| PT (1) | PT1597214E (no) |
| SI (1) | SI1597214T1 (no) |
| WO (1) | WO2004076382A1 (no) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070044686A1 (en) * | 2003-09-19 | 2007-03-01 | Terje Angelskaar | Liquid accelerator |
| US20070054059A1 (en) * | 2003-08-20 | 2007-03-08 | Yasuhiro Nakashima | Spraying material and spray technique employing the same |
| US20070062417A1 (en) * | 2003-05-30 | 2007-03-22 | Terje Angelskaar | Admixture |
| US20070144405A1 (en) * | 2003-09-12 | 2007-06-28 | Martin Weibel | Accelerator composition for accelerating setting and/or hardening of a cementitious compositon |
| US20080090016A1 (en) * | 2004-07-28 | 2008-04-17 | Terje Angelskar | Setting Accelerator For Sprayed Concrete |
| US20100003412A1 (en) * | 2006-07-14 | 2010-01-07 | Martin Weibel | Stable Sprayed Concrete Accelerator Dispersion Having A High Active Substance Content |
| US20100200464A1 (en) * | 2009-02-12 | 2010-08-12 | Todd Dana | Vapor collection and barrier systems for encapsulated control infrastructures |
| US20110041736A1 (en) * | 2008-03-25 | 2011-02-24 | Lafarge | Additives for cement |
| US20110197792A1 (en) * | 2008-01-11 | 2011-08-18 | Martin Weibel | Aqueous Accelerator Mixture |
| US20130008355A1 (en) * | 2011-07-06 | 2013-01-10 | Fmc Corporation | Lithium-based concrete admixtures for controlling alkali-silica reactions with enhanced set-time control and processes for making the same |
| KR101302478B1 (ko) | 2013-03-25 | 2013-09-02 | (주) 에이텍정밀화학 | 광물계 액상 급결제 및 이의 제조방법 |
| US20190071368A1 (en) * | 2016-03-22 | 2019-03-07 | Sika Technology Ag | Accelerator |
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| CN110627397B (zh) * | 2019-08-28 | 2021-11-02 | 四川琪汇新材料有限责任公司 | 一种高强型无碱液体速凝剂、制备方法及其应用 |
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| CN113816639A (zh) * | 2021-09-07 | 2021-12-21 | 宿州市健生矿山设备有限公司 | 一种硫铝酸盐水泥基速凝剂及其制备方法和应用 |
| CN115572099B (zh) * | 2022-10-25 | 2023-06-16 | 中铁十一局集团有限公司 | 一种快硬早强喷射混凝土用无碱液体速凝剂的常温制备方法 |
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Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070062417A1 (en) * | 2003-05-30 | 2007-03-22 | Terje Angelskaar | Admixture |
| US7381264B2 (en) * | 2003-05-30 | 2008-06-03 | Construction Research & Technology Gmbh. | Admixture |
| US20070054059A1 (en) * | 2003-08-20 | 2007-03-08 | Yasuhiro Nakashima | Spraying material and spray technique employing the same |
| US7618490B2 (en) * | 2003-08-20 | 2009-11-17 | Denki Kagaku Kogyo Kabushiki Kaisha | Spraying material and spray technique employing the same |
| US20070144405A1 (en) * | 2003-09-12 | 2007-06-28 | Martin Weibel | Accelerator composition for accelerating setting and/or hardening of a cementitious compositon |
| US7662230B2 (en) * | 2003-09-19 | 2010-02-16 | Construction Research & Technology Gmbh | Liquid accelerator |
| US20070044686A1 (en) * | 2003-09-19 | 2007-03-01 | Terje Angelskaar | Liquid accelerator |
| US20080090016A1 (en) * | 2004-07-28 | 2008-04-17 | Terje Angelskar | Setting Accelerator For Sprayed Concrete |
| US8118930B2 (en) | 2004-07-28 | 2012-02-21 | Construction Research & Technology Gmbh | Setting accelerator for sprayed concrete |
| US20100003412A1 (en) * | 2006-07-14 | 2010-01-07 | Martin Weibel | Stable Sprayed Concrete Accelerator Dispersion Having A High Active Substance Content |
| US20110197792A1 (en) * | 2008-01-11 | 2011-08-18 | Martin Weibel | Aqueous Accelerator Mixture |
| US8075688B2 (en) | 2008-01-11 | 2011-12-13 | Construction Research & Technology Gmbh | Aqueous accelerator mixture |
| US20110041736A1 (en) * | 2008-03-25 | 2011-02-24 | Lafarge | Additives for cement |
| US7998267B2 (en) * | 2008-03-28 | 2011-08-16 | Lafarge | Additives for cement |
| US20100200464A1 (en) * | 2009-02-12 | 2010-08-12 | Todd Dana | Vapor collection and barrier systems for encapsulated control infrastructures |
| US8366918B2 (en) | 2009-02-12 | 2013-02-05 | Red Leaf Resources, Inc. | Vapor collection and barrier systems for encapsulated control infrastructures |
| US20130008355A1 (en) * | 2011-07-06 | 2013-01-10 | Fmc Corporation | Lithium-based concrete admixtures for controlling alkali-silica reactions with enhanced set-time control and processes for making the same |
| KR101302478B1 (ko) | 2013-03-25 | 2013-09-02 | (주) 에이텍정밀화학 | 광물계 액상 급결제 및 이의 제조방법 |
| US20190071368A1 (en) * | 2016-03-22 | 2019-03-07 | Sika Technology Ag | Accelerator |
| US10851023B2 (en) * | 2016-03-22 | 2020-12-01 | Sika Technology Ag | Accelerator |
Also Published As
| Publication number | Publication date |
|---|---|
| BRPI0407787A (pt) | 2006-02-14 |
| KR101097568B1 (ko) | 2011-12-22 |
| NO20054394D0 (no) | 2005-09-22 |
| GB0304158D0 (en) | 2003-03-26 |
| NO342962B1 (no) | 2018-09-10 |
| NO20054394L (no) | 2005-11-25 |
| MXPA05009033A (es) | 2005-11-23 |
| CN100404469C (zh) | 2008-07-23 |
| KR20050107452A (ko) | 2005-11-11 |
| AU2004215680B2 (en) | 2007-12-06 |
| ES2327924T3 (es) | 2009-11-05 |
| PT1597214E (pt) | 2009-07-29 |
| EP1597214A1 (en) | 2005-11-23 |
| EP1597214B2 (en) | 2017-10-11 |
| US20060137576A1 (en) | 2006-06-29 |
| SI1597214T1 (sl) | 2009-10-31 |
| ATE435845T2 (de) | 2009-07-15 |
| ES2327924T5 (es) | 2018-02-20 |
| AU2004215680A1 (en) | 2004-09-10 |
| BRPI0407787B1 (pt) | 2017-10-31 |
| EP1597214B1 (en) | 2009-07-08 |
| DE602004021908D1 (de) | 2009-08-20 |
| CN1753848A (zh) | 2006-03-29 |
| WO2004076382A1 (en) | 2004-09-10 |
| CA2516048A1 (en) | 2004-09-10 |
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